MICROWAVE-ASSISTED RAPID HYDROLYSIS AND PREPARATION OF THIOAMIDES BY WILLGERODT-KINDLER REACTION
摘要:
Aldehydes and aryl alkyl ketones were efficiently transformed to thioamides with the same number of carbon atoms via Willgerodt-Kindler reaction under microwave irradiation in solvent-free conditions. The thioamides obtained were hydrolyzed to corresponding carboxylic acids with microwave dielectric heating in one minute. Both reactions are very fast and the yields are excellent.
The Willgerodt-Kindler Reaction in Water: High Chemoselectivity of Benzaldehydes over Acetophenones
作者:Kioumars Aghapoor、Farshid Mohsenzadeh、Golriz Khanalizadeh、Hossein R. Darabi
DOI:10.1007/s00706-006-0560-7
日期:2007.1
Water has been found for the first time as a useful solvent in the Willgerodt-Kindler (WK) reaction for the synthesis of benzothiomorpholides in high yield at 80 degrees C for 3h. This novel approach confronts the WK protocol with a new situation in which water not only is not regarded as a serious disadvantage but also is applied in this case as a useful solvent in the reaction. The basis of this finding is the presence of a methylene chain in the carbonyl substrates, which leads to the high reaction selectivity of benzaldehydes over acetophenones.
MICROWAVE-ASSISTED RAPID HYDROLYSIS AND PREPARATION OF THIOAMIDES BY WILLGERODT-KINDLER REACTION
Aldehydes and aryl alkyl ketones were efficiently transformed to thioamides with the same number of carbon atoms via Willgerodt-Kindler reaction under microwave irradiation in solvent-free conditions. The thioamides obtained were hydrolyzed to corresponding carboxylic acids with microwave dielectric heating in one minute. Both reactions are very fast and the yields are excellent.
Microwave-Assisted Conversion of Nitriles to Thioamides in Solvent-Free Condition